#!/bin/bash
#
# Additional functions that would mostly just pertain to a Ubuntu + Qemu setup
#

function build_guest_image() {
    exclaim "Actually building the image, params: $@"

    local guest_os=$1
    local guest_release=$2
    local dev_mode=$3
    local guest_username=$4
    local image_output=$5
    local image_type=${image_output##*.}
    local working_dir=$(dirname ${image_output})
    local root_password=${TROVE_ROOT_PASSWORD}

    local trove_elements_path=${PATH_TROVE}/integration/scripts/files/elements
    # For system-wide installs, DIB will automatically find the elements, so we only check local path
    if [[ "${DIB_LOCAL_ELEMENTS_PATH}" ]]; then
        export ELEMENTS_PATH=${trove_elements_path}:${DIB_LOCAL_ELEMENTS_PATH}
    else
        export ELEMENTS_PATH=${trove_elements_path}
    fi

    local GUEST_IMAGESIZE=${GUEST_IMAGESIZE:-3}
    local GUEST_CACHEDIR=${GUEST_CACHEDIR:-"$HOME/.cache/image-create"}
    sudo rm -rf ${GUEST_CACHEDIR}

    export GUEST_USERNAME=${guest_username}
    export HOST_SCP_USERNAME=${HOST_SCP_USERNAME:-$(whoami)}
    export ESCAPED_PATH_TROVE=$(echo ${PATH_TROVE} | sed 's/\//\\\//g')
    export DEV_MODE=${dev_mode,,}

    # In dev mode, the trove guest agent needs to download trove code from
    # trove-taskmanager host during service initialization.
    if [[ "${DEV_MODE}" == "true" ]]; then
        export SSH_DIR=${SSH_DIR:-"$HOME/.ssh"}
        manage_ssh_keys
    fi

    TEMP=$(mktemp -d ${working_dir}/diskimage-create.XXXXXXX)
    pushd $TEMP > /dev/null

    # Prepare elements for diskimage-builder
    export DIB_CLOUD_INIT_ETC_HOSTS="localhost"
    local elementes="base vm"

    # Only support ubuntu at the moment.
    if [[ "${guest_os}" == "ubuntu" ]]; then
        export DIB_RELEASE=${guest_release}
        # https://cloud-images.ubuntu.com/releases is more stable than the daily
        # builds (https://cloud-images.ubuntu.com/xenial/current/),
        # e.g. sometimes SHA256SUMS file is missing in the daily builds website.
        # Ref: diskimage_builder/elements/ubuntu/root.d/10-cache-ubuntu-tarball
        declare -A image_file_mapping=( ["xenial"]="ubuntu-16.04-server-cloudimg-amd64-root.tar.gz" ["bionic"]="ubuntu-18.04-server-cloudimg-amd64.squashfs" )
        export DIB_CLOUD_IMAGES="https://cloud-images.ubuntu.com/releases/${DIB_RELEASE}/release/"
        export BASE_IMAGE_FILE=${image_file_mapping[${DIB_RELEASE}]}
        elementes="$elementes ubuntu-minimal"
    fi

    export DIB_CLOUD_INIT_DATASOURCES=${DIB_CLOUD_INIT_DATASOURCES:-"ConfigDrive"}
    elementes="$elementes cloud-init-datasources"

    elementes="$elementes pip-and-virtualenv"
    elementes="$elementes pip-cache"
    elementes="$elementes guest-agent"
    elementes="$elementes ${guest_os}-docker"

    if [[ -n ${root_password} ]]; then
        elementes="$elementes root-passwd"
        export DIB_PASSWORD=${root_password}
    fi

    # Build the image
    disk-image-create -x \
      -a amd64 \
      -o ${image_output} \
      -t ${image_type} \
      --image-size ${GUEST_IMAGESIZE} \
      --image-cache ${GUEST_CACHEDIR} \
      $elementes

    # out of $TEMP
    popd > /dev/null
    sudo rm -rf $TEMP

    exclaim "Image ${image_output} was built successfully."
}

function clean_instances() {
    LIST=`virsh -q list|awk '{print $1}'`
    for i in $LIST; do sudo virsh destroy $i; done
}

# In dev mode, guest agent needs to ssh into the controller to download code.
function manage_ssh_keys() {
    SSH_DIR=${SSH_DIR:-"$HOME/.ssh"}

    if [ -d ${SSH_DIR} ]; then
        echo "${SSH_DIR} already exists"
    else
        echo "Creating ${SSH_DIR} for ${HOST_SCP_USERNAME}"
        sudo -Hiu ${HOST_SCP_USERNAME} mkdir -m go-w -p ${SSH_DIR}
    fi

    if [ ! -f ${SSH_DIR}/id_rsa.pub ]; then
         /usr/bin/ssh-keygen -f ${SSH_DIR}/id_rsa -q -N ""
    fi

    cat ${SSH_DIR}/id_rsa.pub >> ${SSH_DIR}/authorized_keys
    sort ${SSH_DIR}/authorized_keys | uniq > ${SSH_DIR}/authorized_keys.uniq
    mv ${SSH_DIR}/authorized_keys.uniq ${SSH_DIR}/authorized_keys
    chmod 600 ${SSH_DIR}/authorized_keys
}
